The present invention relates to an artificial snow making equipment for an artificial ski slope wherein a block of ice is pulverized and blown away.
A conventional air-blowing pulverizer such as an ice crusher generates artificial snow 49 by pulverizing ice block 48 into sleet-like small pieces as shown in FIGS. 11 and 12. The equipment in FIG. 11 has rotary blades 45 for pulverizing which are arranged at an equal distance from each other in the radial direction around the rotational shaft in casing 44 on the top of rigid substrate 47. Air supply opening 41, through which air to glow artificial snow 49 is supplied, and ice supply opening 42, through which ice blocks are supplied, are placed at one end of substrate 47 under the lower end of casing 44. The other end of substrate 47 under casing 44, opposite from supply opening 42, has exhaust opening 43 through which artificial snow 49 made of pulverized ice is blown. Ice blocks 48 are supplied, together with air through air supply opening 41 on the substrate at the right side in the figure and are pulverized into sleet-like pieces by crushing them against substrate 47 with the rotational force of rotary blades 45, which are arranged around rotational shaft 46 and rotate at
Another example of a conventional air-blowing pulverizer is shown in FIG. 12. Herein, the positions of supply opening 42 for ice blocks and air supply opening 41 are different from ones in FIG. 11 wherein they are arranged at separate positions on casing 44. Supply opening 42 for ice blocks 48 is placed at the top of casing 44. Supplied ice blocks, while passing through casing 44 by rotary blades 45 for pulverizing which are rotated by rotational shaft 46 at a high speed, are crushed with rotary blades 45 and reach the air supply opening at the bottom of casing 44. The crushed ice is further pulverized between substrate 47 and rotary blades 45 to be artificial snow 49 which is blown with air through exhaust opening 43 at the other end of the bottom of casing 44.
However, the above air-blowing pulverizer has drawbacks. With the pulverizer of FIG. 11, the size of ice pieces pulverized by rotary blades 45 may vary depending on the amount of ice blocks 48 supplied to casing 44 through supply opening. Also, once the supply of ice blocks 48 becomes excessive, the path between air supply opening 41 and exhaust opening 43 may become blocked with snow. Therefore, excess drive is required to rotate rotary blades 45 at a high speed. With the pulverized of FIG. 12, in addition to the drawbacks discussed about the pulverizer in FIG. 11, when one intensifies the air flow through air supply opening 41 to blow the pulverized ice pieces further, not all the air reaches exhaust opening 43, but some air flows backward and tends to leak from supply opening 42. As a result, the air flow to blow artificial snow 49 from exhaust opening 43 is weakened such that artificial snow 49 cannot be blown far enough. Consequently, further drive is required.
Hence, the present invention intends to provide an efficient air-blowing pulverizer in which:
variance in the size of pulverized ice pieces is eliminated by stabilizing the amount of ice blocks to be supplied such that the resulting artificial snow is more desirable for skiing;
operation of the pulverizer is smoothly continued by preventing ice blocks from blocking inside the casing; and
all supplied air can be utilized to blow the pulverized ice pieces far enough without requiring excess drive.
To serve the above purpose, the present invention provides, according to the first invention, an artificial snow making equipment with constant forced-blowing, comprising:
an ice block supplier 1 to supply ice blocks at a constant rate including:
a casing 3 having, on a upper side of the casing, an ice block supply opening 4 through which ice blocks 2 are supplied, and on a lower side of the casing, an exit for ice blocks 5 which is positioned under the casing 3;
a rotary blades 8 which are arranged at an equal distance from each other around a rotational shaft 6, formed at the center of the casing 3, to supply the ice blocks 2 at a constant rate; and
an air-blowing pulverizer 11 including:
an air duct 9 which receives the ice blocks 2 and air 12 being supplied from an ice block supplier 1;
a casing 13 having an opening 10 of the air duct 9 on the side surface;
rotary blades 17 radially arranged at an equal distance from each other around periphery 16 of rotational shaft 15, formed at the center of the casing 13, to pulverize ice blocks 2 into ice pieces 18; and
an air exhaust 19 formed on the opposite side of the casing 13 from the opening 10 of the air duct to blow ice pieces 18 as artificial snow 20,
wherein the exit for ice blocks 5 of the ice block supplier 1 is connected to an ice block receiving slot 14 of air-blowing pulverizer 11 by the air duct 9.
According to the second invention in reference to artificial snow making equipment with constant forced-blowing of the first invention, the ice block supplier 1 is such that space 22 between the periphery of casing 3 and edge 21 of rotary blade 8 is formed to be very narrow to prevent a back flow of air 12 from exit for ice blocks 5 into the ice block supplier 1.
According to the third invention in reference to artificial snow making equipment with constant forced-blowing of the first or second invention, the rotary blades 17 of the air-blowing pulverizer 11 have width 24 equal to the length 23 of rotational shaft 15, and the rotary blades 17 are radially arranged at an equal distance from each other around the periphery 16 of the rotational shaft such that rotary blades 17 are parallel to axis 39.
According to the fourth invention in reference to artificial snow making equipment with constant forced-blowing of the first or second invention, the rotary blades 17 in the air-blowing pulverizer 11 are radially arranged in two rows at an equal distance from each other around the periphery 16 of the rotational shaft, wherein one side of the rotary blades 17, at the central periphery 26 of the shaft, is positioned behind the other side of the rotary blade 17, on an edge 25 of the shaft, in the direction opposite from direction of rotation 27 such that rotary blade 17 is oblique to axis 39.
According to the fifth invention in reference to artificial snow making equipment with constant forced-blowing of the second or fourth invention, edge portion 31 is a portion of rotary blade 17 in air-blowing pulverizer 11 between edge 29 of the blade and bending line 30 which is located between base 28 and edge 29 of the blade wherein edge portion 31 is bent in the direction opposite from direction or rotation 27.
In other words, the means of the present invention has an ice block supplier 1 to supply ice blocks as a raw material at a constant rate to air-blowing pulverizer 11. In this an ice block supplier 1, a plurality of rotary blades 8 are arranged at an equal distance from each other around rotational shaft 6 which rotates inside casing 3. Exit for ice blocks 5 of an ice block supplier 1 to supply ice blocks at a constant rate is placed facing air duct 9 through which air is forced to air-blowing pulverizer 11 such that ice blocks can be supplied to air-blowing pulverizer 11 at a constant rate by adjusting the speed of rotation of rotary blades 8 in relation to the volume of the space between rotary blades 8. Additionally, space 22 between the [inner] periphery of casing 3 and edge 21 of rotary blade 8 is established to be a minimum yet does not cause any disturbance in the rotation of rotary blades 8. This configuration prevents the force of air to air-blowing pulverizer 11 from declining, which is caused by a backflow of air to be supplied to air-blowing pulverizer 11 into ice block supplier 8 to supply ice blocks at a constant rate via exit for ice blocks 5 of an ice block supplier 1 as an opening to supply ice blocks to air-blowing pulverizer 11.
In air-blowing pulverizer 11, a plurality of rotary blades 17 are arranged in the radial direction around rotational shaft 15 which rotates in cylindrical casing 13 at a high speed. Air duct 9 is placed facing the side of casing 13 to form ice block receiving slot 14 which receives ice blocks 2 to be pulverized, as well as forced air. The side of casing 13 opposite from ice block receiving slot 14 is air exhaust 19 through which artificial snow made of pulverized ice pieces 18 is blown out.
In the case of air-blowing pulverizer 11 where rotary blades 17 are alternated in two rows around rotational shaft 15, blade 32 is positioned between one edge 25 of rotational shaft 15 and central periphery 26 of the shaft while blade 33 is positioned between central periphery 26 and the other edge 25. This plurality of blades is alternated in two rows on periphery 16 of the rotational shaft. As a result, ice blocks 2 to be pulverized move between rotary blades 17 from left to right and vice versa as they are transferred to air exhaust 19 such that ice pieces 18 will not block the space between rotary blades 17. This configuration does not require extra drive [as a counter force against the blocked path]. Further, ice blocks 2 are pulverized by rotary blades 17 while moving between rotary blades 17, resulting in more uniformed small ice pieces 18 as artificial snow 20, more appropriate for skiing. Moreover, the side of rotary blades 17 in two rows at central periphery 26 of the shaft is positioned to form an angle alpha in relation to rotational shaft 15 in the direction opposite from the direction of rotation. Consequently, ice blocks 2 can more easily move between two rows of rotary blades 17 such that the pulverizing performance is improved. Additionally, a backflow of the air in casing 13, which would cause a decline in the air pressure, is prevented such that artificial snow 20 can be blow further away.